Automatic polishing machine



Dec. 25, 1956 J. H. INGERSOLL ET AL 2,775,073

AUTOMATIC POLISHING MACHINE Filed Dec. 12; 1951 12 Sheets-Sheet 2 Jamasfifngersoll,

Malia?" Z1). Ker/click, JVases Hqgy, Neal CZJTuzlsar-d w iLea .L. Leuili Dec. 25, 1956 J. H. INGERSOLL ET AL 2,775,073

AUTOMATIC POLISHING MACHINE Filed Dec. 12, 1951 12 Sheets-Sheet 3 D IWW Jams H fryer-5011 \ZbJe /L a. lZ/kifis, Zl/alferll). oualic'k, ffoses Hqgyzl, Heal Q. fiuzLsard: @Lea .L. Leuc'if @amz Q4,

Dec. 25, 1956 J. H. INGERSOLL ET AL 2,775,073

AUTOMATIC POLISHING MACHINE Filed Dec. 12, 1951 12 Sheets-Sheet 4 Dec. 25, 1956 J. H. INGERSOLL ETAL 2,775,073

AUTOMATIC POLISHING MACHINE Filed Dec. 12, 195 1 12 Sheets-Sheet 5 [Tu/suffers erzs'all, -fajep/t. 'Q. Zflkii'e, Zilli'ouajzlcla Neal a. Fuisar'd .MLeo L- Jamesflfrg Malia;-

Dec. 25, 1956 J. H. INGIERSOLL ET AL 2,775,073

AUTOMATIC POLISHING MACHINE Filed Dec. 12, 1951 12 Sheets-Sheet. 7

Dec. 25, 1956 J. H. INGERSOLL ET AL 2,775,073

AUTOMATIC POLISHING MACHINE Filed Dec. 12, 1951 12 Sheets-Shee'l: 8

Dec. 25, 1956 J. H. INGERSOLL ET AL ,7

AUTOMATIC POLISHING MACHINE Q Filed Dec. 12 1951 12 Sheets-Sheet 9 7 .5/ar/er I C017 Ll L2 fnuenl ar-s:

x J95 Jamesfi [n erzs'oll, \fo epk Q. Zl/kii'e Malier llll oualic/i, Mose-5 H gyi, T Neal QJTuclszzrci JPLEO L. Leuizff.

Dec. 25, 1956 J. H. INGERSOLL ETAL 2,775,073

AUTOMATIC POLISHING MACHINE Filed Dec. 12, 195 1 12 slieets sheet 10 fru/ercl o r5:

Leuzlii %mi 6? pww Dec. 1956 J. H. INGERSQLL ET AL 75,

AUTOMATIC POLISHING MACHINE Filed Dec. 12, 1951 iii 1] l2 Sheets-Sheet ll fnvenfars Jamesfi fngensoll, Jqsepk Q. ZU/Lie,

v-aw; fldh Dec. 25, 1956 J. H. INGERSOLL ET AL 7 AUTQMATIC POLISHING MACHINE 1'2 Sheets-Sheet 12 Filed Dec. 12, 1951 ITLZ/GRl OT'S" Moses Hegyc' Jamesfifngersoll, \fosepk a. wha e,

ZZ/alier ZH ff'oz/czlic/ Levzlif.

Uflitd States r AUTOMATIC POLISHING James H. Ingersoll and Joseph A. White, Flossmoor, 111., Walter W. Kovalick, Munster, Ind., and Moses Hegyi, Lansing, Neal A. Ruisard, Chicagoy'and Leo L. Levitt, Blue Island, 11]., assignors to Borg-Warner Corporation, Chicago, 111., a corporation of Illinois Application December 12, 1951, Serial No. 261,324 46 Claims. (Ch 51 -91 This invention relates generally to polishing machines and more particularly to' polishing machines for the purpose of polishing the concave surfaces of earthw'orking-discs for farm machinery.

'Anob ject-of this invention is 'to provide a "durable polishing machine by means of which agricultural tliscs may be polished more expediously and economically than-ever before.

Heretofore, in the polishing of 'earthworkihg discs, even in caseswhere there has been some type of machineto aid therein, the'ususal method of polishing the concave portions or surfaces of these discs has been a rather haphazard manual operation in which the surfaces were polished by' manually moving the 'disc'to and fro under a rotating polishing wheelrn any times to polish-the surface"of the disc sufiiciently. Such la method of operation had to be'repeated each time a disc was to'bepolished. "As a resultt hefeaturesof"anautomatic machine were lost and the surfaces which wereithus crudely polished were a result of more'orjless guess-weir on the part 'of the "operator. Obviouslythe pressure "of thetiisc against the polishing medium and the time of tra'vel of thedisoacrb'ss the polishing surface of the wheel'varie'd from disc to disc and operator toopcr'ator;

-Arp'urpose ofthis inventionis to 'p rovicleanalltomatic machine wherein the discs "are poli'shed,"once placed thereupon, without further operator manipulation and guesswork. 4

' Another goal of this invention is tojprovide a 'support assembly and meansactivatedby thepolishingmember whereby the concave portion "or surface of'an agricultural disc is polished smoothly and qui ckly. "This"ljis accomplished by providing an easy means ofjloa ding "and unloading the discs; by providing a'meanswhereby'the discisbrought by operation of the machine into'prfesshre regulated rotating, polishing engagmen't' with thej,,pnlishin'g' r 2,775,073 Patented Dec. 25, 1956 struction and operation of the present mechanism are understood from the description.

It is preferred to accomplish the numerous objects and purposes of the invention and to practice the same in substantially the manner hereinafter fully described and particularly pointed out in the appending claims.

Thisinvention can briefly be described as an automatic disc polishing machine having a carriage or frame mounted on a track for movement thereon and which supports .a second .or auxiliary rocker frame for move- 5 ment therewith. The carriage is also provided with a rocker frame by means .of a linkage and guide system.

The polishing or spindle cradle is capable of rocking or" arcua'te'ly oscillating with and parallel to the rocker frame, and in addition is capable of moving normal to, he, towards and away from the rocker frame when desired.

A means is provided for causing the polishing cradle to move normal to the rocker frame and comprises a fluid responsive means in combination With a spring pressure means. This combination provides a system for regulating and controlling the polishing and is accomplished by controlling the pressure of the disc against the polishing wheel. Mounted on the polishing cradleis"a 'sp'iiidlemechanism"which comprises a rotatable fluid presure responsive chuck for holding {the ,disc to bepolishedthe'reon. It is a purpose of this chuck mechanism to allow rotation of the disc While being polished and yet maintaining the same firmly in position. To maintain a constant speed'of the disc while being polished agoverning' system is operatively connected to the clutch mechanism.

Briefiy,"the operationof this new automatic disc polishing machine consists of first, the loading or inserting of the'agriculturaldisc inthe fluid responsive chuck or-workholding -rnechanism,*and, second, the pressing of a starter button thus beginning the automatic operation of the machine by causing or having the carriage move to one position on the track, i. -je.,"=und'er'-the polishing wheel by operation of a fluid pressure responsive means. In this positiona switch means 'simiiltaneously'activates a secondfluid'pressure responsive -means which is attached to' 'thepolishing cradle to positionthe latter and the element; and by providing'a means on the machine'wher'e by the disc is causedtomove arcuately transverse to the 5 direction of polishing rotation so that the entire c'oncave surface is completelypolished.

' Another'end of this inventionis to provide amea'ns in a'm'achine of this type whereby the disc, when in polishing position, is governed in its sp eedof rotation. 4 v

Another purpose of this invention is 'toprovide a machine whereby thefagricultural disc isheld for rotjation againstthe polishing element by mean's of aregulated fluid pressure responsive and "spring. pressure responsive system'- This system Provides a"m eans" bY 'which the disc may be evenly polishedi regardless of ditferences of curvature due to redesigning'or because. of

perturbations on thesurfaces thereof caused by the various processes in manufacture, such as temperihgjetc. Another object of this invention "is' toimprovethis class "of machines so "as to increase 'thirdurability, ntilityandefiiciency. I

Additional -objects, aims, accomplishments fand advantages of the invention contemplated herein wil1 be apparent .:to;' persons skilled in the art "after the con disc 7 in' its "polishing position at a predetermined pressure against the polishing wheel. Said switch means simultaneously activates the-power unit which urgesthe rocker frame along its arcuate path. The rocker frame makes one "corhpl'ete'cycle along its arcuate path thus causing the entire concave surface of the disc to be polished by the'polishing wheel. When the rocker frame again returns to its starting position the polishing cradle is again returned-tojts'original position near the rocker frame by means of the activation of the last-mentioned fluid pressureresponsive means. At that time,the polishing cradle, rocker frame and carriage are "returned to, their original loading and unloading position on the track by operation of the first-mentioned fluid pressure responsive means wherein the disc just polished can be unloaded and the machine made readyfor another'disc.

With'these objectsin viewand followed by,a brief description "of-"the machine and its operation, we'have described indetail the physical structure and operation 'ofourinvention together with the other elements and purposes as will be apparent as lthedescription proceeds, the invention residing in" the novel construction, the combination 'of'parts and the arrangement thereof for cooperative effort-more *efliciently' performing the functions required,Fast/illustrated in the drawings and which will be more fully described hereinafter, reference being had to the accompanying drawings, which form a part of this specification, wherein:

Fig. l is a side elevation partlyin section to vshow details of construction of the exemplary form of the disc polishing machine embodying the present invention and shown in operating polishing position;

Fig. 2 is a top plan view of the machine shown in Fig. 1 in a position intermediate its loading position and its working position;

Fig. 3 is a transverse vertical section taken along line 3-3 of Fig. 1 looking in the direction of the, arrows;

Fig. 4 is an enlarged side elevation, partly in section, of the spindle assembly showing details of the fluid pressure responsive chuck or workholding mechanism and its associated governor mechanism;

Fig. 5 is a schematic and diagrammatic drawing of the electrical and fluid pressure circuit at the instant of the depression of the starter button;

Fig. 6 is the schematic and diagrammatic drawing of the electrical and fluid pressure circuit an instant shortly after the starter button is released;

Fig. 7 is a schematic and diagrammatic drawing of the electrical and fluid pressure circuit at the instant the carriage reaches its position beneath the polishing wheel;

Fig. 8 is a schematic and diagrammatic drawing showing the electrical and fluid pressure circuit at the instant the timer mechanism is brought into operation;

Fig. 9 is a schematic and diagrammatic drawing of the electrical and fluid pressure circuit at the instant the rocker frame and the polishing cradle have started on their arcuate path while in polishing engagement with the polishing wheel;

Fig. 10 is a schematic and diagrammatic drawing of the electrical and fluid pressure circuit at the instant the rocker frame returns to its starting position having completed one polishing cycle;

Fig. 11 is a schematic and diagrammatic drawing of the electrical and fluid pressure circuit at the instant the polishing cradle returns to its original position, i. e., at a distance near the rocker frame;

Fig. 12 is a schematic and diagrammatic drawing of the electrical and fluid pressure circuit at the instant of completion of one full operation of the machine with the carriage returned to loading and unloading position and set up for the next operation.

The drawings are to be understood as being more or less of a schematic character for the purposes of disclosing typical or preferred forms of the improvements that are contemplated herein and in these drawings like reference characters identify the same parts throughout the several figures.

Description of the operating mechanism of the machine Referring further in detail to the construction shown in the drawings, there is illustrated the new automatic disc polishing machine made up of the main component parts, namely, a carriage designated in its entirety as 20,

with a rocker frame, designated in its entirety by refere ence numeral 40, mounted thereon and a polishing cradle, designated in its entirety by 80, in turn mounted on the rocker frame, all of which function to automatically cooperate with a rotating polishing wheel P to polish the concave portions of agricultural discs D.

Referring now to Figs. 1 and 3 of the drawings, the carriage or carrier 20, made of U-shaped. irons or other suitable material suitably fixed or welded together, is

adjustahly mounted or supported on wheels 21 by means of a plurality of angle irons 22, pins 23 and slots 24 for movement on rails 25 of a track. A guard 26 is provided for each rail 25 to prevent the wheels 21 of the carriage 20 from jumping or leaving the track during operation. A yoke 27 having base 23, apertured uprights 29 and pins 30 is attached to the floor or ground for pivotally mounting a fluid pressure responsive means 31. Said fluid pressure responsive means comprises a cylinder 32 having piston 33 (see Fig. 3) connected by a piston rod 34 to a yoke or coupling 35 which is pivotally and adjustably connected to the carriage 20 by means of pins 36 through the medium of angle irons 37 secured by bolts 38 or otherwise suitably attached thereto. When the fluid pressure responsive means 31, thus attached, is activated by fluid or air pressure against the piston 33, the carriage will reciprocate or oscillate along the track from a loading and unloading position, such as that generally indicated by the reference letter A, to the position under the polishing wheel P as clearly shown in Fig. 3. Fig. 1 shows this latter or intermediate position by a dashed line indicating the agricultural disc.

Suitably mounted on the carriage 20 for movement therewith is the rocker frame 40 which has two pairs of cam followers 41 and 42 located at opposite ends of the rocker frame 40 and rotatably mounted thereon to engage and cooperate with camming surfaces 43 defined in a pair of cradle cam plates 44 welded or otherwise made integral with the carriage 20; said camming surfaces 43 being located on opposite sides of carriage 20 as more clearly shown in Figure 3. It can readily be seen that the aforementioned ca-mming surfaces 43 provide an arcuate path for the rocker frame 40 with respect to the carriage 20 and that movement along said arcuate path will be substantially at right angles to reciprocatory movement of said carriage. The rocker frame 40 is further provided with extensions 45 to support the pair of cam followers 42 at a higher level so that when the rocker frame 40 is in one position, such as that shown in Fig. 1, said rocker frame is substantially parallel to the carniage 20. A study of Figs. 2 and 3 will show the relation of the cam followers 41 and 42 with respect to the rocker frame 40 and the mounting for the polishing cradle 80.

Referring now to Figs. 1 and 2 which clearly show the driving unit, generally indicated by reference numeral 46, suitably mounted on the carriage 20 for movement therewith. The driving unit has for its purpose the driving of the rocker frame 40 along the arcaute path delined by the camming surfaces 43. The driving unit 46 comprises a motor 47 having ashaft 48, a pinion gear 49 mounted thereon and a driven gear 50 which drives a shaft 51. The shaft 51 and other shafts are suitably rotatably mounted on supports 52 and 53 which are fixedly attached to the carriage. Mounted for rotation on the shaft 51 is a face cam 54 which, when rotated, activates a cam follower arm 55 by means of a cam follower 56 fixedly mounted on one end thereof and cooperating with the camming surfaces of the face cam. This cam follower arm 55 is fixedly mounted on a shaft 57 (the upper sha-ft shown in Fig. 1), the latter being ro- .tatively activated thereby from a position shown in Fig. 1

to position B to drive a driving gear 58 and a driven gear 59. Mounted to rotate with the driven gear 59 is a shaft 60 (the lower shaft shown in Fig. 1) which causes rotation of a rocker arm 61 fixedly mounted thereon. Said rocker arm 61 is adjustably and pivotally connected by a threaded coupling means 62 to one end of a connecting rod 63 by means of pivot block 64 threadably connected to said rocker arm. The other end of the connect-ing rod 63 is pivotally connected to the carriage 20 by means'of pins 65 and a bifurcated yoke or coupling 66 threadably connected thereto. Adjustment of the rocker arm 61 with the rocker frame 40 is accomplished, therefore, by the threaded pivot block 64 and connecting rod 63 with its end coupling or threaded yokes 62 and 66. It can be seen that the driving unit 46 thus con nected to the rocker frame 40 will cause the latter to 44 by operation of the rocker arm 61 between the extreme positions, such as that shown in Fig. 1, to a position indicated by the reference letter C.

A counterweight system, generally designated by reference: numeral 67'; hase-.been provided: form the rocker frame 40. The system comprisees :aaweight 68-: enclosed in aho-usingu69iisuitably weldedor otherwise attached to angle irons v70 andca-rriagezfla Said weight 68 is suitably attached to the rocker frame 40 'by pins 71 and cable 72f.over vsheaves or. pulleys 73 and' 74-mounted on the housing 69 by members 75 and 76, respectively. The operation of" this counterweight system is believed'to be apparent.

The polishing cradle made-of angle irons or other suitable material, is mounted on the=rocker frame 40 by means of followers sl cooperating with-uprights 82 havingslots 83; the latter-for-mingguiding surfaces for the followers 81. The uprights are mounted or otherwise made integral with' the' rocker-frame 40 by welding or other convenient and suitable means. It is apparent that the polishing cradle 80 when tli-us attached'to the rocker frame -40-is capable of moving normal to, i. e., away from and towards therocker frame, and-is also capable of moving in an arcuate path'parallel to thepath of travel ofthe -rocker frame.- Tomaintain the=polishing oradle 80 substantially parallel to the rocker frame at-all times, a

linkage system is provided. Said linkagesystem has one set of-link bars 84 (the-upper bars shown in Fig. 1) pivotally connected at one end to the followers 81 and extensions 85 0f the polishing cradle, and'pivotally connected'atthe other end to a stabilizer arm 86. A'second set of link bars 87 ofthe linkage system (the lower bars in Fig. 1) is at one-end pivotally connected to the stabilizer arm 86 and to the link bars 84, and at the other endis-pivotallyconnected by pins 89 to the rocker frame 40.

Referring now to Fig. 3, and considering the. aforementioned movement of thepolishing cradle normal. to.

the-rocker frame 40; it becomes apparent that said move: ment is caused in partby, and under control of, a pair of fluid pressure responsive means 90 which are pivotally supported at 91 by a mounting bracket 92 comprising angle irons 93 and bars 94. These fluid pressure responsive means '90 have cylinders 95 and pistons '96 reciprocably actuated by fluid pressure and connected by piston rods 97 to a threada-bly adjustable yoke or coupling 98 which in turn is pivotally coupledto the polishing cradle 80 by pins 99. This reciprocation of the piston 96 will ultimately cause .the polishing cradle 80; to be oscillated normal to, i. e., away from or towards-the rocker frame 40 when desired.

A pair of resilient pressure means or springs 100 are adjustably mounted on the rocker frame 40 and connected tothe polishing cradle 80 to counterbalance the polishing cradle; and a work load imposed thereon. and to cooperate with the fluid pressure responsive means 90. The adjustability of this spring mounting is accomplished by means of a telescopic housing 101 having a lower telescopingpart 102 mounted on the rocker frame 40 by means of angle irons 103 and a screw system-104 operatively attached to the base 105. The upper telescoping part 106 of the housing 101 is attached to the polishing cradle 80 by an angular cover 107 secured thereto by bolts 108 orany other suitable means. The adjustable screw system 104, which allows the distance between the rocker frame 40 and the base tobe determined, suitably controls the pressure to be imposed by the spring. The relation between the spring pressure and the fluid pressure responsive means will become apparent in the disclosure of the operation of the automatic disc polishingmachine hereinafter. However,- it is obvious that the. combination of the spring and fluid pressure responsive means will allow a latitude of pressure within a certain range to overcome diificulties that might be encountered by changes in the curvature of discs due to redesigning or perturbations on the surface thereof because of tempering, etc.

A spindle assembly 109 shown in detail in Fig. 4 is mounted upon the polishing cradle 80. Said spindle assembly comprises a rotatable fluid pressure responsive cuticleor:w rkholdinarmechanisma ndvg vernnnmean' enerally esignatedz v reference 1 um rals;l'ltlzand'rl'l at p t y- The: hoker-workhol i g mechanism a; spindle; housing; 112a SUlIZlbI'YF'flHQChGdI by bolts ;;1 tora bracketi:base;-114- on th5pO1lShil1g cradle 80.; '[ihes spindle-housing; 1-12 supports arotatable; fluidwor airv cylinder 115, hayinggareciprocable' piston; 1 16" Wit-117a}: piStOllyl'Od: orcentershaft 117 attached-thereto. Held; within; said housing y 112? ;by. means of ,-a pair ofibearingst 1-18, suitably mounted: therein, is a spindle shaft 119; axially encompassing the; piston: rodaand zkeyed-thereto; by pin 120;. The piston; rod'may: be divideddntq' segements;,and-have;a bolt 121 axially centrally. located there-1, in to vary theplengthof. the pistonrod; ifdes ired',f;byvthe; mere substitution"of--aq1ongen or shorter segment; for the 'OIlCilD. operations At-. the, end;=of-thepiston;;rod-, oppositethe piston:- 11.6:. iS'yar head; membcn-LZZZhaV Hgt'QZ; peripheral recess 123 to permita-;G-shaped washen-mem i ber 124-.to .beinserted, thereon :whendesired; Qbv-iously the slot of the,C.=shaped-washermemberymustbe smallen.

than the: outside: diameter of the 'headmember andgyet; largejenoughjtofit snugly in'therecess 1-23 therefor, thusbeing-capablemf exerting a clamping orclutch-ing-action; on the work loador discuponactivation-of-the;.piston;

, 1 16-'as;- wil1fbe apparent. Thus, when an agricultural'disc;

D is placedover; the head member 122 and the crShaPCdg washer 124- issinserted in the recess-12'3' and the; piston: 1-16'is caused to reciprocate bysuitable air -.pressure'made,z-. available, to the cylinder through the double ;a i'r conduit: 125, the disc D is clamped against the platen 126 fixedly; mounted by:bolts; 12.7' to the spindle shaft -1'19.'thereby allowing it to :rotate therewith; It is apparent that move-; ment of the piston andi the centershaftiin the oppositet direction-.will cause the; disc -D to be; released or. 1111-, clamped from: the chuck; or,-workholding mechanism;

When'the disc D.is=in-lo cked or-clamped-position and; said spindle assembly is brought into operating position, aswill hereinafter be explained, the rotatable fluid pressure responsive chuck orworkholdingmechanism 1-10::is; caused to rotate by frictional polishing-engagement with-f the polishing "Wheel P, clearly shown in- Figs; 1 and-3;: The chuck or workholding mechanism thus allows, the: disc D torotate and at the same time maintains-thesame in clutching relation.

To govern the speed of rotation of the disc D-when:the"

sameis in fractional engagingpositionwith the-polishing;

. or bracket 114 and which transmitstorque to the governor mechanism 111;. Said governor mechanism: hasnar governor gear 133 fixedly attached, to a rotatable shaft; 134 and a pair of bearings. 135 suitablymountedima: housing 136. Said housing is suitably fixedly-attachedtosaid bracket or base 114 of the polishing cradle. Fixedly attached by aset pin 137 is an upper or first yoke 138 to which a pair of governor arms 139 are pivotally supported inwardly of their ends by pins; 140. Said governor arms are also pivotally connected through a pair of toggle arms 141 to a lower or secondyoke'142. axially reciprocable on the governor shaft Mounted; on the ends opposite of the weighted ends of the governor: arms 139 is a pair of, brake shoes 143-. which willv frice; tionally engage the outer side of the shaft'housing 136; thus causing the frictional brake to ultimately preventthe disc D from rotating beyond a desired speed, by, centrifugal deflection of said governor arms away from; the governor shaft.

Description of the operation of the new automatic disc polishing machine Having thus given a detailed description of the opcrating' mechanismof theqnew automatic disc polishingmachine, a normal cycle or. sequence. of operation willbe explained herein.

7 [An operator loads an unpolished "disc on the spindle assembly 109 by placing the same over the head member 122, inserting the C-shaped washer member 124 in the recess 123, and fluid pressure moves the piston 116 thereby clutching the disc against the platen 126 of the chuck or workholding mechanism 110. A starter button 144, shown schematically in Figs. -12, is closed and the carriage 20 moves along the track from the loading position A, as shown in Fig. 3, to a position under the polishing wheel by the actuation of the pressure responsive means 31. Upon reaching this position, a limit switch 145, shown conveniently mounted on the track in Fig. 3, is closed by a plunger 146 mounted on the carriage 20, which simultaneously activates the fluid pressure responsive means 90 causing the polishing cradle 80 to move normal to, or away from, the rocker frame 40. Said limit switch 145 simultaneously causes activation of the power or driving unit 46 for driving the rocker frame 40 along its 'arcuate path. The rocker arm 61 of the power unit 46 is in the position generally designated as C in Fig. 1 at the beginning of the cycle or when loaded, and will move through activation of the power unit 46 to a position shown in Fig. 1 and then return to its original or starting position C whereupon an actuating arm 147 actuating arm 147 actuated by rocker arm 61 closes limit switches 148 and 149, suitably and conveniently mounted on the carriage 20, causing the polishing cradle 80 and its associated spindle assembly 109 to drop, i. e., to return to'its original or starting position nearest the rocker frame 40.

It is obvious that the resilient pressure means or springs 100 and the fluid pressure responsive means 90, in combination, will give control to the amount of pressure made available to the system against which the disc D is forced to be maintained in frictional polishing relation with the polishing wheel P. It can further be seen that slight changes of curvature or perturbations on the surface of the disc D will tend to increase the amount of pressure against the polishing wheel and will be sufliciently absorbed by the spring system. This combination provides for many modifications in the general outline or curvature of the disc.

The dropping of the polishing cradle 80 activates a limit switch 150 suitably and conveniently mounted on the rocker frame 40 (see Fig. 1) by flexure of the linkage system. The latter limit switch causes the fluid pressure responsive means 31 to return the carriage to its original loading position. At this position, the operator can remove the polished disc and again reload the platen 126 with another unpolished disc and begin a second cycle of operation. This cycle, of course, can be repeated as many times as desirable. Notable, therefore, among the many advantages residing in the use of this machine is the complete lack of operator guesswork involved in the usual manual polishing operation.

Description of the electrical and fluid pressure circuit for the operation of the new automatic disc polishing machine Each of the Figs. 5 to 12 are to be followed in consecutive numerical order in order to enable an understanding of the sequence of operation of the machine in its entirety. To facilitate the understandability of the electrical and fluid pressure circuits continuous heavy lines indicate a completed circuit through the various relays, switches and valves at a particular instant in time during the sequence of operation and the dotted heavy lines indicate the component parts of the fluid pressure circuit that are under pressure from a suitable source simultaneously with the complete circuit in its accompanying electrical diagram. Furthermore, to further aid in the understanding of each step in the sequential operation the electrical and fluid pressure circuits are traced through each terminal, connection, relay, etc. from its source of supply.

' Referring now to Fig. 5 there is shown the electrical and fluid pressure circuits with their associated schematic elements of the machine at the position in the sequence of operation wherein the disc D has been loaded on the platen 126 and the starter button 144 has been depressed by the operator. This diagram is to be considered, however, at that instant inmmediately before there is any actual movement of any armatures, switches, etc. because ofthe energization of solenoids. In other words, the circuits shown in Fig. 5 are exactly the same as they were at the end of the last polishing operation with the exception that the circuit immediately completed by the depression of the starter button is also shown in its energized condition. It can be seen from this diagram; that the carriage 20 diagrammatically represented by wheel 21 is in the loading position A as shown in Fig. 3; the rocker arm 61 is in its starting position C as shown in Fig. l; and the polishing cradle is in its down position nearest to the rocker frame 40. Thus, this schematic and diagrammatic illustration discloses an electrical current brought from a suitable source of supply, generally indicated by reference letters L1 and L2, through a fuse box having terminals 161 and 162. The depression of this starter button 144, as hereinbefore mentioned, will complete a circuit from terminal 161 through connection 163, through solenoid 164 of a relay 165, through terminal 166, through the starter button 144 and a stop button 167, thus energizing the solenoid 164. It is also apparent that a second complete circuit is maintained independently of the starter button from terminal 162 through connection 168, through connection 169, through an armature and the now closed contacts 171 of the solenoid relay 172, through the now closed contacts 173 on armature 174 of the solenoid relay 165, through a solenoid 175 of the solenoid relay 176, through the now closed contacts 177 of the limit switch 149 (mounted on carriage 20 as shown in Fig. 1), through the now closed contacts 178 of the limit switch 150 (mounted on the rocker frame 40 as shown in Fig. 1), through connections 179, 180, 181, 182 and terminal 183 on timer mechanism 184, through connection 163 back to terminal 161. A third circuit is also completed from terminal 162 through connections 168 and 169, through the now closed contacts 185 of the armature 186 of the relay 176, through a solenoid 188 of the four-way solenoid valve 189, through the connections 190 and 191 and ultimately to terminal 161, thus energizing the solenoid 188. A further circuit is completed from the connection 191 through solenoid 192 of the bleeder valve 193, through now closed contacts 194 of the armature 186, through connection 169 and ultimately to terminal 162, thus energizing the bleeder valve solenoid 192.

Simultaneously therewith, a suitable source of air pressure is made available from conduit 195 into a manually operable control valve 196 and to the conduit 197 thus keeping the piston 116 of the chuck or workholding mechanism 110 in its clutching position. The lower portion of cylinder 115 below the piston 116 at this time is open and a bleed circuit is complete through conduit 198 and exhaust port 199 on control valve 196. Conduits 197 and 198 represent schematically the double air conduit 125 shown in Fig. 4. Air pressure is also made available from conduit 195 through conduit 200. through the four-way solenoid valve 189, through conduit 201 into the left end portion of the cylinder 32 maintaining, at the right or in position A as viewed in Fig. 3, the entire assemblage on the carriage 20. At the same time a conduit on the left end of cylinder 32 is open through exhaust port 203 because of the continued energization of solenoid 188. Simultaneously, air pressure is made available from the conduit 195, through the four-Way solenoid valve 204, which is presently spring biased by spring 205 to suply pressure to conduits 206, 207 and 208, respectively, to maintain the polishing cradle 80 at its lower position by application of air pressure against the pistons 96. The lower ends of the cylinders 95, connected to bleeder valve 193, are bled to exhaust through conduits 209, 210, 211 and exhaust port 212 .because of the energization of solenoid 192,

armors With reference to Fig. 6, which is taken in the next instant of time following the movement of the armature 17411116. to the energization of, the relay 165, it is to be noted that de-energization of the relay 176 has been accomplished as will be hereinafter explained. Because of the, movement of the armature 174 thus opening the contacts 173 the circuit to relay 176 is broken. Now a circuit is complete. from terminal 162, through the stop button 167, through now closed contacts 213 of the limit switch 148 through now closed holding contacts 214 on the armature 174 to terminal 161, thus holding and maintaining the solenoid 164 energized. A second circuit from terminal 162 is completed, through connection 168, through the now closed contacts 215 on the armature 174, through a solenoid 216 on the four-way solenoid valve 189to connection 180, which is ultimtely connected -to terminal 161 on the fuse box 160. Simultaneously therewith fluid or air is made available from conduit 195, through conduit 200 to the solenoid valve 189 and the conduit 202, beginning the movement of piston 33 in cylinder 32 to the left, or from A as viewed in Fig. 3, and simultaneously air pressure is exhausted from the left end of the cylinder 32 through conduit 291, the valve 189 and the exhaust port 203. The reversal of the flow of air pressure through the valve 189 has been accomplished by energization of solenoid 216 and de-energization of solenoid 188. All other features in the fluid pressure circuit remain the same with the exception of the bleeder valve 193 which is now closed by de-energization of solenoid 192 thereby closing off the exhaust port 212 thereof.

Now with respect to Fig. 7 which is taken at that instant of time when the carriage (represented by wheel 21) is in its working position on the track, i.- e.,.in the position immediately beneath the polishing wheel P as shown in Fig. 3 of the drawings. Fig. 7 shows an additional circuit maintained from the terminal 162, through one terminal of the stop button 167, through the now closed contacts 217 of the limit switch 145, through a terminal 218, through a solenoid 219 and terminal 183, thus energizing the solenoid 219 of the timer mechanism 184. All other features in the electrical and fluid pressure circuit remaining substantially the same.

Referring now to Fig. 8 which is taken at that time immediately after the solenoid 219 on the timer mechanism 184 has been energized and the contacts 220 and 221 have been closed thereby. It is to be noted that a circuit can be traced from terminal 162, through connections 168 and 169, through connection 223, through the now closed contacts 220 to energize the motor M on the timer switch mechanism. Another complete circuit can be traced from terminals 161, 163, and 183, through a connection 182, through the now closed contacts 221, through a connection 224, through a colenoid 225 of the relay 172, through connection 218 and the now closed contacts 217 of limit switch 145, through the one terminal of the stop button 167 and terminal 162, thus energizing the solenoid 225. The fluid pressure circuits remain the same at this time.

Referring now to Fig. 9 which is an instantaneous diagrammatic and schematic view of the circuit immediately after the energization of the solenoid 225 and movement of armature 170 of the relay 172. All other circuits remaining substantially the same. This figure shows that current can be traced from terminal 162, through connection 168, through contacts 215, of the armature 174 or" the relay 165 maintaining the solenoid 216 of the four-way solenoid valve 189 energized by completing a circuit through connection 189, ultimately to terminal The circuit through contacts 221 of the timer mechanism 184 and connection 224 to hold the relay 225 energized is maintained. Another circuit is completed from terminal 162 and connections 168 and 169, through the now closed contacts 226 on armature 170, through 10; a toggle switch zemireu n solenoid 22s of thefom way solenoid valve" 204; through connection 190 ult imatel'yback to terminal- 161 to energize the solenoid- 228' thus; opening-the valve 204. A further circuit can be; traced from the-energizedarmature 170, through the contacts 229 thereon, through the starter coil 230 of the motor 47 (on carriage 20),, through the connection 181 ultimately back to; terminal, 161': Energization of'the starter coil 230 will .start the, rockerarm 61 in motion.

Simultaneously with theenergization of solenoid 228: of the four-way solenoid valve 204 air pressure is made available from conduit 195, through the valve 204', through conduit 231', through an adjustable reducing valve 232 into the lower-partiofl cylinders byway of conduits 209, 210' and 211. Admission of air pressure will thereupon begin the movement of piston 96 upwardly. Energization of solenoid 228falso opened the upper portion of the cylinders 95through conduits 206, 207' and 208, valve 204 and exhaust port 233 thereon. All other fluid pressure circuits remain the same.

Referring now to Fig. 10 which is taken at an instant shortly, after that time represented in Fig. 9 during which themotor 47 actuated the rocker arm 61 causing the rocker frame 40 to begin its arcuate. path of travel and shortly after the euergization of the solenoid 228 of the valve 204. It. is to benoted that the rocker arm 61 changed its position with respect to the limit switches 148 and 149. and that. the spindle cradle 80 has moved upwardly. It. is noted? also that the conduit 209 is connected; to a meter. 234 which indicates the amount of pressure made available to the underside of pistons 96 thus giving an accurate indication of the pressure at which the disc D is held against the polishing wheel P. Obviously, this pressure can be regulated. as desired by the adjustable reducing valve 232', and' is a combination of pressure exerted by the springs and the air acting under pistons 96. As: the rocker arm 61 moved away from the limit. switches 1'48 and 149 the contacts 213 and 177 thereof respectively were opened and contacts 235 were closed. A complete circuit may, therefore, be traced fromtheterminal162, through connections 168 and 169, through the contacts 236 on armature 170, through the relay solenoid 225,, through the now closedv contacts 235 of the limit switch 148, through connection 180 ultimately to terminal 161. Notable also is the de-energization of relay by-theopening of contacts 213. Although it isevident that'the solenoid 219 of the timer mechanism 184 has been maintained energized, the motor M thereof hasbeenset to open the contacts 220 and 221 after apredetermined, interval, normally four or five seconds. It is the function of this timer mechanism 184', as is evident fromthe schematic and diagrammatic draw,- ing of the electrical circuit, to become a bridging circuit for maintaining the solenoid 225' energized long enough to bridge the interval in time between the energization of starter coil 230 of motor 47 and the closing of contacts 235 on limit switch 148 by operation of rocker arm 61. It is, obviously, important that solenoid 225 be maintained energized during that time. After the closing of contacts 235 there is no further function of the timer mechanism. The electrical and fluid pressure circuits as disclosed in Fig. 10 all remain the same throughout the greater portion of the polishing cycle wherein the rocker frame travels from a position B to the position of the machine in Fig. l and returns to position B.

Referring now to Fig. 11, there is shown the electrical and fiuid pressure circuits upon completion of a cycle of the rocker frame. It is noted that the rocker arm 61 has again opened contacts 235 and has again closed contacts 213 of the limit switch 148 and has closed contacts 177 of limit switch 149; The opening of contacts 235 caused de-energization of the solenoid 225 of relay 172, thus ultimately de-energizing the starter coil 230 of the motor47 and solenoid 228 of the four-way solenoid valve 204. Obviously, this de-energization of the solenoid 228 allowed the spring 205 to bias the valve 204 so that air pressure could be emitted from conduit 195 into conduits 206, 207 and 208. Since this latter air pressure does not go through a reducing valve, such as 232; its value will be higher than the pressure in the lower part of the cylinder and will begin to move the pistons 96 downwardly to lower the polishing cradle 80.

The downward motion of the polishing cradle 80 will again close the contacts 178 of the limit switch 150 by flexure of links 84 and 87 and a complete circuit can then be traced through the again closed contacts 171 and 173 on armatures 170 and 174, respectively, through the solenoid 175 or relay 176, through contacts 177 and 178 of limit switches 149 and 150, respectively, and through connection 179 ultimately to terminal 161. This circuit again energized solenoid 175 and closed contacts 185 and 194 so that solenoid 192 of bleeder valve 193 and solenoid 188 of the four-way solenoid valve 189 are again energized.

The bleeder valve 193 thus allows air pressure to be bled from the cylinders 95 through conduits 209, 210 and 211, and exhaust port 212 so that the polishing cradle will lower completely. Energization of solenoid 188 makes pressure available from conduits 195 and 200 through the valve 189, conduit 201 and into the left side of cylinder 32, and at the same time opens the right side of cylinder 32 to exhaust port 203 through conduits 202.

Fig. 12 shows the schematic and diagrammatic electrical and fluid pressure circuits subsequent to the movement of the piston 33 in cylinder 32 to the right thus moving the carriage 20 therewith to position A in Fig. 3. Obviously, this opens the contacts 217 of the limit switch 145 and prepares the entire machine for unloading and reloading. The circuits in this figure are the same as those shown in Fig. with the exception of the energization of the solenoid 164 by depression of the starter button 144.

The operator can then remove the polished disc by manual operation of the manually operable valve 196 causing air to be emitted from conduit 195 through conduit 198 into cylinder 115 thus releasing the chuck or workholding mechanism and insert a new unpolished disc on the spindle assembly.

If at any time during a cycle of operation the operator desires to stop the machine, this stoppage or safety feature is provided by the proper placement of the stop button 167 and the toggle switch 227.

The embodiment of the invention shown herein is disclosed as utilizing air as the operating fluid in the fluid pressure system. It is contemplated, however, and to be distinctly understood, that any other system utilizing fluid, such as oil for example, or any system utilizing vacuum in all or portions thereof may be used equally as well and are within the purview of this invention.

From the foregoing description it is apparent a new automatic disc polishing machine is provided incorporating electrical and fluid responsive means effective to automatically control various stages of the work operations of the machine while providing instrumentalities operative to stop the machine manually at the will of the operator. The importance of the automatic features of this machine cannot be over-emphasized.

While this invention has been described in detail in its exemplary form or embodiment, it will be apparent to persons skilled in the art, after understanding the improvements, that various changes and modifications may be made therein without departing from the spirit or scope thereof. It is aimed in the appended claims to cover all such changes and modifications.

We claim:

1. In a polishing machine having a polishing medium; means including reciprocating means for moving an unpolished article to be polished between a first position of loading and unloading and a second intermediate position; means including oscillating means for moving said unpolished article between said second intermediate position and a third position of polishing engagement with a polishing medium and capable of maintaining the article in said third polishing position; and means including driving means for oscillating said unpolished article along an arcuate path when said third article is in said polishing position to accomplish polishing of said article while in said third polishing position, said oscillating means being capable of returning said polished article to said second intermediate position, and said reciprocating means being capable of returning said polished article to said first position to complete the polishing cycle of said machine. 2. In a polishing machine; means defining a carriage; means operatively associated with said carriage for transmitting oscillations thereto between a loading position and a working position; means defining a rocker frame; means including camming means connecting said rocker frame to said carriage and defining an arcuate path of oscillatory movement of said frame with respect to said carriage; means including driving means mounted on said carriage and associated with said frame for oscillating said frame along said arcuate path when said carriage is in working position; means defining a polishing cradle; means connecting said cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movement normal to the latter; means mounted on said frame and associated with said polishing cradle for imparting oscillations to the latter when said carriage is in working position; and means including work holding means mounted on said cradle for holding the article to be polished.

3. In a polishing machine; means defining a carriage; means including fluid pressure responsive means operatively associated with said carriage for transmitting oscillations thereto between a loading position and a working position; means defining a rocker frame; means including camming means connecting said rocker frame to said carriage and defining an arcuate path of oscillatory movement of said frame with respect to said carriage; means including driving means mounted on said carriage and associated with said frame for oscillating said frame along said arcuate path when said carriage is in working position; means defining a polishing cradle; means connecting said cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movement normal to the latter; means mounted on said frame and associated with said polishing cradle for imparting oscillations to the latter when said carriage is in its working position; and means including workholding means mounted on said cradle for holding the article to be polished.

4. In a polishing machine; means defining a carriage; means operatively associated with said carriage for transmitting oscillations thereto between a loading. position and a working position; means defining a rocker frame; means including camming means comprising cradle cam plates and cam followers operatively associated therewith and connecting said rocker frame to said carriage and defining an arcuate path of movement of said frame with respect to said carriage; means including driving means mounted on said carriage and associated with said frame for oscillating said frame along said arcuate path when said carriage is in working position; means defining a polishing cradle; means connecting said cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movement normal to the latter; means mounted on said frame and associated with said polishing cradle for imparting oscillations to the latter when said carriage is in working position; and means including workholding means mounted on said cradle for holding the article to be polished.

5. In a polishing machine; means defining a carriage; means operatively associated with said carriage for transmitting oscillations thereto between a loading position and'aworkingposition; means defining a.rocker"'frarne;" means including camming means connecting said rocker.

frame totsaid carriage and defining an arcuate path of oscillatory movement of said frame with. respect to said carriage; means including driving means comprising. an.

oscillationsto thelatter when said carriage is in working position; and means including, workholding means mounted on said cradlefor 'holdingrthe article to bev polished;

6.-In a polishing machine; means defining a carriage; meansoperatively associated with said carriage for transmining-oscillations thereto between a loading position and a working position; means defining ,a rocker frame; meansincluding 1camming means connectingsaid rocker frame to said cradle. and defining an arcuate path for oscillatory movement of said frame with respect to said carriage; means including driving means comprising. an oscillatable rocker arm, face cammingmeans for oscillating said rocker arm and a motor for driving said face camming means mounted on said carriage and associated with said frame for oscillating said frame along said arcuate path when said carriage is in working position; means defining a polishing cradle; means connecting said cradle and said frame for parallel movement withrespect to said frame and allowing oscillatory movement normal;

to saidframe; means mounted on saidframe and associated with said polishingcradle for imparting said oscillations to the latter when said carriage is in working position; and means including Workholdingmeans mounted on said cradle for holding the article tobe polished; and

means including electrical and fluid. pressure responsivemeans for effecting automatic operation of said machine;

7. Ina polishing machine; means defining a carriage; means. operatively associated with said carriage for transmitting oscillations thereto between a loading position and a working position; means defining a rocker frame;

means including camming means connecting said rocker frame to said carriage and defining an arcuate path for oscillatory movement of said frame with respect to said carriage; means including driving means mounted on said carriage and associated with said frame for'oscillating said frame along said arcuate path when said carriage is in working position; means defining a polishing cradle; means including. guide and follower means and linkage means connecting said cradle to said frame for parallel movement with respect to said frame and allowing oscil' latory movement normal to the latter; means mounted on said frame and associated with said polishing cradle for imparting said oscillations to the latter when said carriage is in working position; and means including workholding means mounted on said cradle for holding the article to be polished.

8. In a polishing machine; means defining a carriage; means operatively associated with said carriage for transmitting oscillations thereto between a loading position and a working position; means defining a rocker frame; means including camming means connecting said rocker frame to said carriage and defining an arcuate path for oscillatory movement of said frame with respect to said carriage; means including driving means mounted on said carriage and associated with said frame for oscillating said frame along said arcuate path when said carriage is in working position; means defining a polishing cradle; means connecting said cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movementxnorma-l to -the latter; means including fluid pressure responsive means mounted -"on said-frameand? associated with said polishing cradle-for imparting said oscillations to "the latter when-said carriageis in working position; and means including workholding means mountedon said cradle' for holding the' article to" be polished;

93*lira-polishirigmachine; means defining'a carriage;

means operatively associated with saidcarriage for trans-- -mitting oscillations thereto-between a loading positioncarriage; 'rneansincluding driving means mounted on said.

carriage and associated with 'said framefor oscillating saidframe along saidarcuate path when said carriageis-inworking position; means defining a polishing cradle; meansconnecting-saidcradle: to said frame-for parallel movement with respect to said frame-endallowing oscillatory movement normaltothe latter; means mounted on saidframe-and associated with said polishing cradle for imparting said oscillations to the latterwhen said carriage is in: working-positiomand means-including workholding means having fiuid pressure responsive chuck means mountedon said cradlefor holding the article to be polished:

10." In a polishing machine; means defining a carriage; means operatively associated with said carriage for-transmittingoscillationsthereto between a. loading position and a working position; means defininga rocker frame; means including cammingmeans connecting said rocker frameto said carriage. anddefining an: arcuate. path. for oscillatory movementofisaid frame withrespect-to said carriage; meansincluding drivingmeans mounted on said carriage and associated with said frame for oscillatingsaid frame alongisaid'arcuatepathzwhensaid carriage is in working position; means defininga polishing-cradle; means connecting saidcradle tousaid framefor parallel movement with respect to said frameland allowing oscillatory movementnormal to the-latter; meansmounted onsaid frame and -associated1 with said polishing cradle for. imparting saidaoscillations toithe latter when said'carr-iage is in working position; andtmeans'including workholding means having .fiuid pressureresponsive chuckmeans. and governor meansamounted; onsaid cradle for holding and governing. the article to. bespolished.

ll... Inia polishingmachine; means defining a carriage; meansrincluding fluidypressure responsive means operativelyassociated withsaidcarriage for transmitting oscillations-thereto between. a loading position and a working-position; means including electrical responsive means; meansdefining arockenframe; means including camming means. comprising cradle cam. plates and cam followers operatively associated therewith connecting said rocker frameto: said. carriage and defining an arcuate path for oscillatory movement of said, frame with respect to said carriage; means. including driving means mounted on carriage for moving said frame along said arcuate pathv when saidcarriage is in workingv position and comprisingan: oscillatable. rocker arm, face cammin g means for oscillating said rocker arm, and a motor'for driving said face camming means, and electrical responsive means connected to said first. mentioned electrical responsive means and actuated by said carrier when said carrier reaches working position; means defining a polishing cradle; means including guide and follower means and linkage means connecting said cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movement normal to the latter; means. mounted on said frame and associated with said polishing cradle for imparting oscillations to the latter when said carriage is in working position and comprisinga second'fl'uid pressure responsive means, resilient means and electrical responsive means connected to said first mentioned electrical means when the carriage; is in working position; and workholding means including a fluid pressure responsive chuck means and governor means mounted on said cradle for governing and holding the article to be polished. h p

12. In a polishing machine; an oscillatable carriage; means operatively associated with said carriage for imparting oscillations thereto; a rocker frame; means connecting said rocker frame to said carriage and defining an arcuate path for oscillatory movement of said frame with respect to said carriage; driving means mounted on said carriage and connected to said frame for oscillating said frame along said arcuate path; a polishing cradle; means connecting said polishing cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movement normal to said frame; means associated with said frame and with said cradle for imparting oscillations to said cradle; and rotatable workholding means mounted on said cradle for holding the article to be polished. V

13. In a polishing machine; an oscillatable carriage; means including fluid pressure responsive means operatively associated with said carriage for imparting oscillations thereto; a rocker frame; means connecting said rocker frame to said carriage and defining an arcuate path for oscillatory movement of said frame with respect to said carriage; driving means mounted on said carriage and connected to said frame for oscillating said frame along said arcuate path; a polishing cradle; means connecting said polishing cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movement normal to said frame; means associated with said frame and with said cradle for imparting oscillations to said cradle; and rotatable workholding means mounted on said cradle for holding the article to be polished.

14. In a polishing machine; an oscillatable carriage; means operatively associated with said carriage for imparting oscillations thereto; a rocker frame; means including cradle cam plates connecting said rocker frame to said carriage and defining an arcuate path for oscillatory movement of said frame with respect to said carriage; driving means mounted on said carriage and connected to said frame for oscillating said frame along said arcuate path; a polishing cradle; means connecting said polishing cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movement normal to said frame; means associated with said frame and with said cradle for imparting oscillations to said cradle; and rotatable workholding means mounted on said cradle for holding the article to be polished.

15. In a polishing machine; an oscillatable carriage; means operatively associated with said carriage for imparting oscillations thereto; a rocker frame; means connecting said rocker frame to said carriage and defining an arcuate path for oscillatory movement of said frame with respect to said carriage; driving means including camming means and rocker arm operatively associated therewith mounted on said carriage and connected to said frame for oscillating said frame along said arcuate path; a polishing cradle; means connecting said polishing cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movement normal to said frame; means associated with said frame and with said cradle for imparting oscillations to said cradle; and rotatable workholding means mounted on said cradle for holding the article to be polished.

16. In a polishing machine; an oscillatable carriage; means operatively associated with said carriage for imparting oscillations thereto; a rocker frame; means connecting said rocker frame to said carriage and defining an arcuate path for oscillatory movement of said frame with respect to said carriage; driving means mounted on said carriage and connected to said frame for oscillating said frame along said arcuate path; a polishing cradl means including guide and follower means and link means connecting said polishing cradle to said frame for imparting oscillations to said cradle; and rotatable workholding means mounted on said cradle for holding the article to be polished.

17. In a polishing machine; an oscillatable carriage; means operatively associated with said carriage for imparting oscillations thereto; a rocker frame; means connecting said rocker frame to said carriage and defining an afcuate path for oscillatory movement of said frame with respect to said carriage; driving means mounted on said carriage arid connected to said frame for oscillating said frame along said arcuate path; a polishing cradle; means including guide and follower means, link means, and stabilizing means connecting said polishing cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movement normal to said frame; means associated with said frame and with said cradle for imparting oscillations to said cradle; and rotatable workholding means mounted on said cradle for holding the article to be polished.

18. In a polishing machine; an oscillatable carriage; means operatively associated with said carriage for imparting oscillations thereto; a rocker frame; means connecting said rocker frame to said carriage and defining an arcuate path for oscillatory movement of said frame with respect to said carriage; driving means mounted on said carriage and connected to said frame for oscillating said frame along said arcuate path; a polishing cradle; means connecting said polishing cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movement normal to said frame; means including fluid pressure responsive means associated with said frame and with said cradle for imparting oscillations to said cradle; and rotatable worltholding means mounted on said cradle for holding the article to be polished.

19. In a polishing machine; an oscillatable carriage; means operatively associated with said carriage for imparting oscillations thereto; a rocker frame; means connecting said rocker frame to said carriage and defining an arcuate path for oscillatory movement of said frame with respect to said carriage; driving means mounted on said carriage and connected to said frame for oscillating said frame along said arcuate path; a polishing cradle; means connecting said polishing cradle to said frame for oscillatory movement normal to said frame; means includingfluid pressure responsive means and spring means associated with said frame and with said cradle for imparting oscillations to said cradle; and rotatabie workholding means mounted on said cradle for holding the article to be polished.

20. In a polishing machine; an oscillatable carriage; means operatively associated with said carriage for imparting oscillations thereto; a rocker frame; means connecting said rocker frame to said carriage and defining an arcuate path for oscillatory movement of said frame with respect to said carriage; driving means mounted on said carriage and connected to said frame for oscillating said frame along said arcuate path; a polishing cradle; means connecting said polishing cradle to said frame for parallel movement with respect to said frame and allowing oscillatory movement normal to said frame; means associated with said frame and with said cradle for imparting oscillations to said cradle; and rotatable workholding means including fluid pressure responsive chuck means mounted on said cradle for holding the article to be polished. v

21. In a polishing machine; an oscillatable carriage; means operatively associated with said carriage for imparting. oscillations thereto; a rocker frame; means connecting said rocker frame to said carriage and defining an arcuate pathfor oscillatory movement of said frame 

